Slides in this set
Numerous research methods have · To show that the brains of murderers
found that violent offenders have who pleaded not guilty by reason of
poorer brain functioning than controls, insanity were different to the brains
but until recently it hasn't been of non murderers.
possible to localise which brain areas · Raine specifically hypothesised that
in particular may be dysfunctional in seriously violent offenders would
violent offenders. have localised brain dysfunction in
areas such as the prefrontal cortex,
amygdala, and the thalamus (the
areas linked to violence)…read more
· 41 murderers pleading not guilty by reason of insanity (NGRI) who were all
charged with murder or manslaughter.
· 39 were male and 2 were female
· There was a control group matched on age, sex and other factors; for example
6 of the criminals pleading NGRI had schizophrenia and so 6 people with the
condition were selected as part of the control group
· None of the control group had
committed murder.…read more
· All participants were kept medication free
for 2 weeks. Urine samples confirmed this
at the time of scanning.
· The control group were matched with the
participants in great detail, eg the patients
with schizophrenia were matched to
controls with the same conditions.
· 14 of the murderers were non-white, and
when compared with the white murderers
they showed no significant difference (on
· Tests were undertaken to ensure that being
left or right handed had no effect on
· Thermoplastic head holder
· PET scanner to image brain functioning (Positron emission tomography)
· Fleurdeoxyglucose (FDG) tracer injected to trace brain metabolism. (The tracer
attaches itself to glucose being used in the brain. Its radioactive so the glucose can be picked up
and mapped by the scanner)
· Continuous performance task (CPT) that was done to make the frontal lobes
work especially hard. The test involved spotting targets on a screen and pressing
a button to indicate that the target had been seen. This lasted for 32 minutes.…read more
· 10 minutes before the FDG injection the participants were given practice trials
on the continuous performance task so that they knew what to expect.
· 30 seconds before the injection a trial task was started so that the initial task
novelty would not be recorded.
· After being injected they were monitored for
30 minutes and were scanned in the PET
· If there's a high glucose metabolism then
more glucose is being used and this will show
up more red on the scan. If the glucose
metabolism is low it will show up blue on the